Robust Setae Research Articles

A new deep-sea species of genus Bathypisella (Crustacea: Peracarida: Amphipoda) from bathyal soft bottoms, south-western Gulf of Mexico

ABSTRACT A new deep-sea species of the genus Bathypisella was collected from bathyal soft bottoms, SW Gulf of Mexico. This new species represents the second Bathypisella species known worldwide, which is characterised by head subequal in length to pereonal segments 1–2 combined, eyes absent, toothed pleonal and urosomal segments, 4-articulate accessory flagellum, coxae 1–4 posteroventral area slightly notched; coxa 4 posterior lobe absent, maxilliped palp article 3 in right angle, maxilla 1 inner plate with five lateral setae, left mandible with three teeth on lacinia mobilis, gnathopod 1 palmar margin convex, gnathopod 2 propodus palmar margin concave, one long, robust seta in palmar angle, epimeron 3 with trifid posteroventral margin, and telson cleft half its length. Besides a complete description of the new species, a dichotomous key to identify both Bathypisella species is provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:73A22DCA-2692-4C24-B008-E01F8E130B69

New Genera and Species of Trigonidiidae (Orthoptera: Grylloidea) from the Mid-Cretaceous of Myanmar with a Redescription of Birmaninemobius hirsutus.

The abundance of insects in Burmese amber illustrates a highly diverse insect community from the mid-Cretaceous period; yet, records of crickets (Grylloidea) are notably scarce. In this study, we describe two new genera with three new species, Palaeotrigonidium concavoculus gen. et sp. nov., Palaeotrigonidium defectivus sp. nov., and Tricalcaratus longilineus gen. et sp. nov., based on three specimens collected in north Myanmar. These new species can be placed within the Trigonidiidae (Orthoptera: Grylloidea) by their triangular head, compound eyes that protrude in dorsal view, and a body entirely covered with robust setae, particularly noticeable in the head and pronotum; however, subfamily assignments are not possible. Another known species, Birmaninemobius hirsutus, Xu et al., 2020, from Myanmar amber is redescribed based on a new specimen and a recheck of the holotype.

Taxonomic notes on the genus Baetiella Uéno, 1931 (Ephemeroptera, Baetidae), with description of three new species from Thailand.

Based on material recently collected in northern Thailand, the present study provides an updated of the genus Baetiella, including Gratia. It comprises six species in Thailand, three of them being new species: Baetiella (Gratia) narumonae, Baetiella (Gratia) sororculaenadinae, Baetiella (Baetiella) bispinosa, Baetiella (Baetiella) baeisp. nov., Baetiella (Baetiella) lannaensissp. nov. and Baetiella (Baetiella) bibranchiasp. nov.Baetiella (Baetiella) baeisp. nov. can be distinguished from other species by the reduction of the posteromedian protuberances on abdominal tergites I-III, the asymmetrical coniform terminal segment of labial palp, the distal margin of abdominal sternites VII-X each with a row of long, spatulate setae, the dorsal margin of femur with two long, robust setae distally. Baetiella (Baetiella) lannaensissp. nov. is diagnosed by the posteromedian protuberances present on tergites I-VIII, dorsal margin of femur with a regular row of long, rounded, ciliated setae and body surface covered with numerous, dense, rounded scale-like setae. Baetiella (Baetiella) bibranchiasp. nov. can be separated from other species by coxal gills present at the base of forelegs and midlegs. The molecular study based on the mitochondrial gene COI and a larval key to species of Thai Baetiella are also provided.

On a small collection of amphipods (Crustacea, Amphipoda) from Chilika Lake with the description of three new species and a new genus

The current study was conducted on the basis of a small collection of amphipods made from Chilika Lake that contained 4 species. Three were described as new species, including one new genus: Parhyale kalinga sp. nov., Chilikorchesta chiltoni gen. nov. sp. nov. and Grandidierella rabindranathi sp. nov., while a fourth one was a previously reported species: Quadrivisio bengalensis Stebbing, 1907. Parhyale kalinga sp. nov. can be differentiated from its closely related congeners Parhyale basrensis Salman, 1986 and Parhyale darvishi Momtazi & Maghsoudlou, 2016 by having male gnathopod 2 propoduswith 2 robust setae at the base of the palm and 2 small setae slightly behind the palm and dactylus much smaller than palm. Chilikorchestia chiltoni gen. nov. sp. nov. can be differentiated from the closely related genus Morinoia Lowry & Myers, 2019 by its incrassate male antenna 2 and untapered telson. Grandidierella rabindranathi sp. nov. can be differentiated from its closely related congeners G. mahafalensis Coutière, 1904 and Grandidierella nioensis Myers, Sreepada & Sanaye, 2019 by having male gnathopod 2 carpus oval shaped with both margins convex.

Two new species of Sarothrogammarus (Crustacea, Amphipoda) from Swat Valley, Pakistan

Two new species of the genus Sarothrogammarus Martynov, 1935 are described and illustrated from Pakistan. Sarothrogammarus miandamensis sp. nov. is characterized by the oval eyes; pereopod III having filtrative setae on merus, carpus and propodus; uropod III terminal article distinct and inner ramus scale-shaped; and having robust setae and slender setae on urosomites I–III. Sarothrogammarus kalamensis sp. nov. can be distinguished from the above species by pereopod III having filtrative setae on merus, but few on carpus and propodus. Detailed morphological characteristics, as well as comparisons with closely related species are provided. Molecular phylogenetic analyses suggest that S. miandamensis sp. nov. is clustered with S. kalamensis sp. nov., with a genetic distance of 19% for COI between the two species.

A new species of the genus Caprella Lamarck, 1801 (Crustacea, Amphipoda, Caprellidae) from Korea

A new species of the genus Caprella, belonging to the family Caprellidae, has been collected from the East Sea of Korea. The new species, Caprella megabranchia sp. nov., is morphologically similar to C. brevirostris Mayer, 1903, in terms of the shape of the propodus of gnathopod 2 and pereopods 5–7, propodi lacking grasping robust seta. However, the new species can be easily distinguished from C. brevirostris by its entirely circular gills and the anterior convexity of peduncular article 3 in antenna 1. The new species is illustrated and compared to related species C. brevirostris and a key to the Caprella species in Korea is also provided.

Caribbean Amphipoda (Crustacea) of Panama. Part II: parvorder Hadziidira.

Amphipods in the parvorder Hadziidira are typically associated with algae, sponges, or coral rubble. Members of the parvorder have a gnathopod 2 that is stouter than gnathopod 1, a pair of dorsal robust setae on urosomite 2, and a basofacial robust seta on the uropod 1 peduncle. Within the parvorder, six families are documented from Bocas del Toro, Panama, represented by 26 species. This research documents range extensions for all 26 species and an identification key to the species of Caribbean Hadziidira of Panama is provided.

Two New Species of Elaphoidella (Copepoda, Harpacticoida) from Subterranean Waters in Northeast Thailand, with a Record of a Gynandromorphic Specimen and an Up-to-Date Key to Elaphoidella Species from Southeast Asia

Two new species of copepods of the genus Elaphoidella Chappuis, 1929 were discovered in a cave and a spring in northeastern Thailand. The first species, E. phuphamanensis sp. nov., belongs to species-group VII sensu Lang. It is most similar to E. turgisetosa Petkovski, 1980 in the armament of the male third exopod of the fourth swimming leg and the shape and armament of the fifth swimming leg in both sexes. However, it is easily distinguished from other congeners by the segmentation of the first swimming leg, the endopod of the fourth swimming leg, and the armature of the third exopod of swimming legs 2–4 in both sexes. The second species, E. propecabezasi sp. nov., is located in species-group I sensu Lang, where the male does not have a transformed seta on the third exopod of the fourth swimming leg and the female fifth swimming leg has four baseoendopodal robust setae, unequal in length. It is most similar to E. cabezasi Petkovski, 1982 and E. paraaffinis Watiroyram, Sanoamuang and Brancelj, 2017 in having the same armature formula as endopods 1–2 of female swimming legs 1–4. However, the ornamentation of the anal operculum, the shape of the caudal ramus, and the armature of the fifth swimming leg in both sexes distinguish them from each other. A rare gynandromorphic specimen of E. propecabezasi sp. nov. was recorded, and a revised key to Elaphoidella species in Southeast Asia is provided.

A new species of amphipod of the genus Parhyale Stebbing, 1897 from Chilika Lagoon, India.

A new species of the genus Parhyale, Stebbing 1897 was collected from the intertidal region of Chilika Lagoon associated with the seaweed Gracilaria sp. Parhyale odian sp. nov. differs from other species of the genus by having a stout robust seta on the surface of the propodus near to dactyl hinge of male gnathopod 1. With the new description of P. odian sp. nov., the global species number in the genus rises to 16.

A new species of amphipod of the genus Demaorchestia Lowry & Myers, 2022 (Senticaudata, Talitridae) from Chilika Lagoon, east coast of India.

The genus Demaorchestia Lowry & Myers, 2022 comprises five species globally. This paper adds a new species D. alanensis sp. nov. to this group, thus increasing the total number of global species to six. The sample was collected from the shoreline of Chilika Lagoon near Barkul, east coast of India. The new species can be distinguished from the other members of the genus by having two or three groups of robust setae on the anterior margin of the propodus of gnathopod 1. With the description of this new species, the article further confirms the occurrence of the subfamily Platorchestiinae and the genus Demaorchestia along Indian coast.

A new species of sponge-inhabiting amphipod, Leucothoe jimi sp. n. (Amphilochidea: Leucothoidae) from Gujarat state, India

ABSTRACT A new species of sponge-inhabiting amphipod belonging to the family Leucothoidae Dana, 1852 is described from Gujarat, India. Leucothoe jimi sp. n. can be differentiated from two closely related species, L. denticulata Costa, 1851 and L. spinicarpa Abildgaard, 1789, by the presence of two marginal robust setae on the outer plate of maxilla 1, in having a straight and short mediofacial setal row on the propodus of gnathopod 2 and in having a different shape and number of setae of the epimera. A total of five species of Leucothoe Leach, 1814 are now reported from India. http://www.zoobank.org/urn:lsid:zoobank.org:pub:86E747D5-65A5-49F6-85DF-3BF2A72B60DC

Morphological and Molecular Study of the Fish Parasitic Crustaceans Cymothoa indica and Mothocya collettei (Isopoda: Cymothoidae), with New Distribution Records

Cymothoidae are parasitic isopods that infest fishes inhabiting marine, brackish, and fresh-water environments. The systematics, distribution, and host specificity of cymothoids is often unknown. In this study, morphological observations and molecular analysis using the COI and 16S rRNA genes were conducted on a juvenile individual of Cymothoa indica infesting the wide-banded hardyhead silverside, Atherinomorus lacunosus, and an ovigerous female of Mothocya collettei infesting the hound needlefish, Tylosurus crocodilus, both collected from Okinawa Island, Japan. This is the first time that these two species of cymothoid have been collected in the Ryukyu Islands, and the juvenile C. indica in particular represents a new northern range limit for its species. That specimen was identified using molecular analysis and showed almost identical morphology to previously reported juveniles, but it differed in the numbers of robust setae on pereopods 6 and 7. The ovigerous female of M. collettei showed a high morphological similarity to M. collettei but had some morphological traits consistent with Mothocya affinis. DNA analysis indicated that these two nominal species of Mothocya are very closely related, and morphological and molecular studies using larger populations of both are needed.

A new deep-sea species of Renella (Amphipoda: Lysianassida: Pakynidae) from the Sea of Okhotsk.

A new amphipod species, Renella lowryi sp. nov., from the north-eastern slope of the Sea of Okhotsk (Russian Far East) is described. The new species is assigned to the genus Renella Lowry & Stoddart, 2012 because it is similar to the species of this genus in the main characters: in the structure of the mouthparts, the structure of gnathopods 1 and 2, corner of palm of gnathopod 1 with the complex of robust seta, pereopods 37, the shape of epimeron 3, uropods and telson. The new species similar to Renella sculptidentata (Ren, 1991) by the structure of antennae 1 and 2, mandible, maxilla 2 and maxilliped, but differs from it by the missing eyes, by the morphology of maxilla 1 outer plate: with 9 setal-teeth in 6/3 arrangement (in R. sculptidentata with 11 setal-teeth in 7/4 arrangement), by the shape of propodus of gnathopod 1 with medially convex anterior margin (in R. sculptidentata anterior margin straight medially), by the shape of propodus of gnathopod 2 with oblique distal margin (in R. sculptidentata distal margin is perpendicular), by the shape of basis of pereopod 5 with rounded posterior wing (in R. sculptidentata posterior wing subrectangular), by the weak armament of the anterior margin of the basis of pereopod 5 and anterior margin of merus of pereopods 57 (in R. sculptidentata anterior margins with few long setae), by the length of inner ramus of uropod 3 which subequal to proximal segment of outer ramus in length (in R. sculptidentata inner ramus shorter than proximal segment of outer ramus). Keys to the world species of the genus Renella is provided.

Talorchestia buensis sp. nov. (Senticaudata, Talitridae), a new species of amphipod from West Bengal, east coast of India.

In coastal regions, Talitrids are found among decaying material in the supralittoral zone of sandy beach, mangroves and delta regions. Five genus and five species of the family Talitridae have been reported so far from Indian coastal waters. A new species of the amphipod genus Talorchestia Dana, 1852, Talorchestia buensis sp. nov. was collected from Kadirabad Char, West Bengal, east coast of India. The species was collected from a sandy beach, beneath dead leaves. The new species can be distinguished from other described species of the genus by the presence of a double rows of setae on the endopod of uropod 2, the presence of more than 10 robust setae in each lobe of the telson, antenna 2 reaching more than half the body length, pereopod 7 longer than pereopod 6 and by the absence of a distal protuberance on the palm of male gnathopod 2. The present article increases the total number of world species in the genus to 26.

Two new species of Eurydice Leach, 1815 (Crustacea: Isopoda: Cirolanidae) from the Andaman Islands, northern Indian Ocean

ABSTRACT Eurydice andamanensis sp. nov. and Eurydice mohani sp. nov. are described from intertidal sandy beaches of South Andaman, Andaman Islands. Eurydice andamanensis sp. nov. can be identified by the posterior margin of pleotelson being one-fourth of the pleotelson in width, weakly convex with 11 plumose marginal setae and 4 robust setae; appendix masculina 0.8 times as long as endopod, projecting slightly beyond endopod distal margin by one-third of its length, distally broad, widely rounded, curved medially and mesial margin with 4 small acute cuticular scales; Eurydice mohani sp. nov. can be identified by the posterior margin of pleotelson with 6 plumose marginal setae, pleotelson without distinct depression on anterodorsal surface; appendix masculina 0.4 times as long as endopod, projecting beyond mid-region of endopod by 0.02 of its length, lateral margin with a sinuate notch and apex is rounded. http://www.zoobank.org/urn:lsid:zoobank.org:pub:AFF18D66-4CE3-4D73-BAAA-39083D542008

A new bathyal species of Pardaliscoides (Amphipoda, Amphilochidea, Pardaliscidae) from off the southwestern Gulf of Mexico.

A new species of pardaliscid amphipod is described and illustrated from a single male specimen collected from bathyal sediments (2125 m depth) in the southern Gulf of Mexico. The new species is morphologically closest to Pardaliscoides fictotelson Barnard, 1966, previously documented from Southern California, at 218 m depth. The new pardaliscid differs from other species in the genus in having antenna 1 with a 10-articulate accessory flagellum; maxilliped palp very long; pereopods 5-7 elongate, slender; basis pereopod 7 expanded; telson with a short U-shaped cleft and pointed lobes; uropods 1-2 outer ramus curved, peduncle flat, longer than rami; uropod 3 rami flat, fleshy-lined, with marginal distal short robust setae. An identification key for all known species in the Pardaliscoides genus is also provided. The new species increase the number of Pardaliscoides species documented to six worldwide.

Mothocya kaorui n. sp. (Crustacea: Isopoda: Cymothoidae), a fish-parasitic isopod with unique antennules from the Izu Islands, Japan.

A new species of fish-parasitic isopod in the family Cymothoidae is described from the Izu Islands, Japan. Mothocya kaorui n. sp. is reported from the gill cavities of the keeled needlefish, Platybelone argalus platyura (Bennett). Despite its unique morphological characters, such as completely article-fused antennules, mitochondrial DNA analysis indicated that it belongs to Mothocya Costa. The new species is clearly distinguished from all other species of Mothocya by having completely fused, stout antennules and partially fused, slender antennae; maxilla mesial lobe with 3 or 4 recurved robust setae, lateral lobe with 4-6 recurved robust setae; maxilliped with 5-8 robust setae on article 3; coxae 2 and 3 wide; black subtriangular pleotelson; and black uropods.

Two new temporary ectoparasitic isopods (Cymothoida: Cymothooidea) from Korean waters with a note on geographical distributions of Rocinela Leach, 1818 and Gnathia Leach, 1814.

Two new species of temporary ectoparasitic isopods, Rocinela excavata sp. nov. and Gnathia obtusispina sp. nov., are reported from the southern Islands of the Korean Peninsula. Rocinela excavata sp. nov. is distinguishable from its related species by the following characteristics: (1) laterally stepped rostrum; (2) separated eyes; (3) propodal blade having eight robust setae; and (4) merus having four or five blunt robust setae in pereopods 1-3. Gnathia obtusispina sp. nov. differs from its congeners by the combination of the following characteristics: (1) body covered with numerous tubercles and setae, (2) cephalon having tooth-like paraocular ornamentations; and (3) frontal border having two inferior frontolateral processes. These two new species are the 13th Rocinela species and 19th Gnathia species in the temperate Northern Pacific region, respectively. Discovery of these new species represents high species diversity of the genera Rocinela Leach, 1818 and Gnathia Leach, 1814 worldwide as well as in the Northern Pacific region. In addition, faunal diversity analysis on the members of both genera revealed that Rocinela species show high-latitude diversity whereas Gnathia species have low-latitude diversity.

First record and a new species of Foxiphalus Barnard, 1979 (Crustacea: Amphipoda: Phoxocephalidae) from the Atlantic Ocean, with two new records of the family from northeastern Brazil

A new species of Foxiphalus Barnard, 1979 is described. The material examined was collected as part of the project "Avaliação da biota bentônica e planctônica da Bacia Potiguar e Ceará" (BPOT), off northeastern Brazilian continental slope on the state of Rio Grande do Norte at depths ranging from 135 to 283 meters. Foxiphalus potiguara sp. nov. is recognized among its congeners by: rostrum slightly exceeding the article 2 of antenna 1; lower lip outer lobes with strong shoulder cusps; maxilliped inner plate with two apical robust setae; gnathopod 2 carpus shortened; pereopod 5 basis tapering distally; and epimeral plate 3 posterior margin weakly crenulated. This is the first record of Foxiphalus for the Atlantic Ocean and we provide an amended diagnosis of the genus and an identification key to its world species. In addition, two new records of Phoxocephalidae are reported from northeastern Brazil: Heterophoxus shoemakeri Andrade & Senna, 2020 and Metharpinia dentiurosoma Alonso de Pina, 2003.

A new species and record of Biancolina Della Valle, 1893 (Amphipoda, Senticaudata, Ampithoidae) from the Southwestern Atlantic

Here we describe a new species of Biancolina from Pernambuco, Brazil, found in association with the brown algae Sargassum spp., between 0.5 and 1.0 m depth. The new species differs from its congeners mainly by the following combination of characters: antenna 1 twice the length of antenna 2, lacinia mobilis present in both mandibles, article 4 of the maxilliped bulbose; coxa 6 with anteroventral lobe well developed as in posteroventral lobe, peduncle of uropod 1 weakly setose, palm of pereopods 5-7 lacking robust seta. This is the first record of Biancolina from the southwestern Atlantic.